Income Taxes Income Taxes (Tax Cuts and Jobs Act) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Reduction to Regulatory Liability due to return of unprotected excess ADIT	$ 273	$ 776
Entergy Arkansas [Member]
Net Regulatory Liabilities for Income Taxes	487	605
Protected Excess ADIT	490	521
Unprotected Excess Accumulated Deferred Income Taxes	9	117
Reduction to Regulatory Liability due to return of unprotected excess ADIT	126	368
Entergy Louisiana [Member]
Net Regulatory Liabilities for Income Taxes	531	612
Protected Excess ADIT	797	812
Unprotected Excess Accumulated Deferred Income Taxes	242	295
Reduction to Regulatory Liability due to return of unprotected excess ADIT	39	141
Entergy Mississippi [Member]
Net Regulatory Liabilities for Income Taxes	237	246
Protected Excess ADIT	261	271
Reduction to Regulatory Liability due to return of unprotected excess ADIT	0	159
Entergy New Orleans [Member]
Net Regulatory Liabilities for Income Taxes	59	86
Protected Excess ADIT	62	59
Unprotected Excess Accumulated Deferred Income Taxes	9	25
Reduction to Regulatory Liability due to return of unprotected excess ADIT	14	13
Entergy Texas [Member]
Net Regulatory Liabilities for Income Taxes	253	352
Protected Excess ADIT	228	237
Unprotected Excess Accumulated Deferred Income Taxes	83	171
Reduction to Regulatory Liability due to return of unprotected excess ADIT	87	15
System Energy [Member]
Net Regulatory Liabilities for Income Taxes	143	163
Protected Excess ADIT	186	202
Unprotected Excess Accumulated Deferred Income Taxes	0	4
Reduction to Regulatory Liability due to return of unprotected excess ADIT	$ 7	$ 80